Fluid couplings



P 1964 0. K. KELLEY 3,149,466

FLUID COUPLINGS Original Filed Dec. 23, 1952 INV EN TOR.

ATTORNEY United States Patent 3,149,466 FLUTE) COUYLINGS Oliver K.Kelley, Bloomfield Hiils, Mich assignor to General Motors Corporation,Detroit, Mich, a corporation of Delaware Original application Dec. 23,1952, Ser. No. 327,568, new Patent No. 2,981,126, dated Apr. 25, 1961.Divided and this appiication Feb. 23, 1961, Ser. No. 91,021

17 Claims. (Cl. 69-64) This invention relates to fluid couplings andmore particularly to hydramatic fluid couplings of the type used withgearing for automotive vehicles. This application is a division of myco-pending application Serial No. 327,568, filed December 23, 1952 forPower Shifting Multi-Step Transmissions, now Patent No. 2,981,126 issuedApril 25, 1961.

In automotive transmissions utilizing gearing combined with a fluidcoupling, it is customary to drive the pump or impeller of the fluidcoupling by the source of power such as the engine of the vehicle. Theturbine or runner of the coupling is usually connected to parts of thegearing in such fashion that when a torque train is establishedtherethrough, rotation of the pump or impeller by the engine will causedrive of the turbine or runner and consequently drive of the output ofthe transmission to move the vehicle. If it is desired to keep thetorque train established even while the engine is idling, a conditionknown as creep can occur if the coupling has torque capacity sufiicientto transmit torque at low engine speed.

An object of the present invention is to provide a fluid coupling ofsuch type that transmission of torque thereby at low input speed can beinterrupted or substantially reduced.

Another object of the invention is to provide a fluid coupling of suchcharacter as to have incorporated therein means for interrupting orreducing the flow of fluid between the pump and turbine at low pumpspeed to interrupt or reduce the torque transmitted by the coupling.

A further object of the invention is to provide a fluid coupling havingincorporated therein plungers mounted in the pump or impeller biased toimpede the flow of liquid between the vanes thereof at low pump speedand centrifugally moved out of the path of flow when the pump speedreaches a predetermined value.

Other features, objects and advantages of the invention will becomeapparent from the following drawings where- FIGURE 1 is a verticalsection of half of a fluid coupling embodying the invention, and

FIGURE 2 is a section taken substantially on the line 22 of FIGURE 1.

Referring now to the drawing, indicates generally the pump or impellerof a fluid coupling which is to be driven by a source of power such asthe engine of an automotive vehicle. The pump or impeller comprises anannular outer shroud 12, an annular inner shroud 14 and vanes or blades16 therebetween. The outer shroud 12 may have an extension 13, afragment of which is shown, for connection to the source of motivepower. The turb ne or runner indicated generally at 20 comprises anannular outer shroud 22, an annular inner shroud 24 and vanes 26 securedbetween the inner and outer shrouds.

The pump 10 has a cage 28 attached to the inner shroud 14 for rotationwith the pump. A number of plungers 30 are mounted in tubular bores ofthe cage as shown in the drawing for sliding movement therein. Theplungers 30 normally are spring-pressed toward the inner part of theouter shroud 10 by springs 32. These springs 3,l49,4fl5 Patented Sept.22, 1954 "ice 32 have parts thereof surrounding stationary pegs 34secured in the cage 23 and parts thereof fitting within the hollowed outplungers 30. The number of plungers used in the coupling may varydepending on the speed at which it is desired the coupling to transmittorque. As shown in FIGURE 2, a plunger 30 is positioned between eachadjacent pairs of pump blades 16.

The springs 32 are of such character that they will maintain theplungers 30 in the position shown in the drawings when the pump 10 isstationary and also when it is rotating at a relatively slow speed suchas idling speed of the engine. These plungers occupy such space betweenadjacent pump blades as to materially interrupt or reduce thecirculation of liquid between the pump 10 and the turbine 20. It will beobvious that while liquid can be discharged from the pump 10 at theouter portion thereof into the turbine 20, the plungers will interferewith return of fluid from the turbine to the pump. However, when thepump 19 is driven at a predetermined speed, such as when the engine isaccelerated to drive the vehicle, centrifugal force will cause theplungers 30 to slide outwardly in their respective bores in cage 28against the resistance of the springs 32. These plungers can be causedto slide into position wherein they are retained entirely within thecage and oflier no impediment to fluid circulation between the pump andthe turbine.

From the foregoing it will be seen that the present invention providesnovel means for controlling the transmission of torque by a fluidcoupling so that at low pump speed, corresponding to engine idlingspeed, substantially no torque will be transmitted by the coupling whileat engine speed high enough to drive the vehicle, such transmission oftorque is not effected.

The invention is to be limited only by the scope of the followingclaims.

I claim:

1. In a fluid drive for transmitting torque, a driving member, a drivenmember, a bladed pump rotor connected to the driving member and a bladedturbine rotor connected to the driven member and mounted for rotation,said pump and turbine rotors having inner and outer shrouds definingtoroidal fluid flow passages between said shrouds and said blades, thefluid flow passages of said turbine rotor receiving liquid from thefluid flow passages of said pump rotor and returning liquid to said pumprotor, and blocking means including a blocking member mounted on a rotorfor movement between a first position at least partially blocking saidfluid flow passages and a second position substantially within saidinner shrouds unblocking said fluid flow passages, biasing means mountedon a rotor and located in all positions entirely within said outershrouds for engaging said blocking member to urge said blocking memberfrom one to another of said positions and centrifugal force responsivemeans mounted on a rotor and located in all positions entirely withinsaid outer shrouds for moving said blocking member from said anotherposition to said one position.

2. The invention defined in claim 1 and said movement of said blockingmember being straight line reciprocating movement.

3. The invention defined in claim 1 and said first position of saidblocking member which is mounted on a rotor being nearer the axis ofrotation of said rotor than said second position.

4. The invention defined in claim 1 and said first position of saidblocking member which is mounted on a rotor being nearer the axis ofrotation of said rotor than said second position and said centrifugalforce responsive means being the mass of said blocking member.

5. The invention defined in claim 1 and said blocking member, saidbiasing means and said centrifugal force responsive means in said secondposition of said blocking member being located entirely within saidinner shrouds.

6. The invention defined in claim 1 and said blocking member, saidbiasing means and said centrifugal force responsive means being mountedon one rotor.

7. In a fluid drive for transmitting torque, a driving member, a drivenmember, a bladed pump connected to the driving member and a bladedturbine connected to the driven member and mounted for rotation, saidpump and turbine having inner and outer shrouds defining toroidal fluidflow passages between said shrouds and said blades, the fluid flowpassages of said turbine receiving liquid from the fluid flow passagesof said pump and returning liquid to said pump, and blocking meansincluding a blocking member mounted on said pump for movement between afirst position at least partially blocking said fluid flow passages anda second position substantially within said inner shrouds unblockingsaid fluid flow passages, biasing means mounted on said pump and locatedin all positions entirely within said outer shrouds for engaging saidblocking member to urge said blocking members from one to another ofsaid positions and centrifugal force responsive means mounted on saidpump and located in all positions entirely within said outer shrouds formoving said blocking member from said another position to said oneposition.

8. The invention defined in claim 7 and said first position of saidblocking member being nearer the axis of rotation of said pump than saidsecond position.

9. The invention defined in claim 7 and said first position of saidblocking member being nearer the axis of rotation of said pump than saidsecond position and said centrifugal force responsive means being themass of said blocking member.

10. The invention defined in claim 7 and said blocking member, saidbiasing means and said centrifugal force responsive 'means in saidsecond position of said blocking member being located entirely withinsaid inner shrouds.

11. In a fluid drive for transmitting torque, a driving member, a drivenmember, a bladed pump connected to the driving member and a bladedturbine connected to the driven member and mounted for rotation, saidpump and turbine having inner and outer shrouds defining toroidal fluidflow passages between said shrouds and said blades, the fluid flowpassages of said turbine receiving liquid from the fluid flow passagesof said pump I said outer shrouds for moving said blocking member fromsaid first position to said second position.

12. The invention defined in claim 11 and said blocking member, saidbiasing means and said centrifugal force responsive means in said secondposition of said blocking member being located entirely within saidinner shrouds.

13. In a fluid drive for transmitting torque, a driving member, a drivenmember, a bladed pump connected to the driving member and a bladedturbine connected to the driven member and mounted for rotation about anaxis, said pump and turbine having inner and outer shrouds definingtoroidal fluid flow passages between said shrouds and said blades, thefluid flow passages of said turbine receiving liquid from the fluid flowpassages of said pump and returning liquid to said pump, and blockingmeans including a blocking member mounted on said pump for substantiallyradial movement with respect to said axis of rotation between a firstposition at least partially blocking said fluid flow passages and asecond position substantially within said inner shrouds, unblocking saidfluid flow passages, said first position being nearer said axis ofrotation than said second position, biasing means mounted on said pumplocated in all positions entirely within said outer shrouds for engagingsaid blocking member to urge said blocking members from said secondposition to said first position and centrifugal force responsive meansmounted on said pump and located in all positions entirely within saidouter shrouds for moving said blocking member from said first positionto said second position.

14. The invention defined in claim 13 and said centrifugal forceresponsive means being the mass of said blocking members.

15. The invention defined in claim 13 and said block member in saidsecond position being entirely within said inner shrouds.

16. The invention defined in claim 13 and said blocking member beingmounted for reciprocating movement in a straight line.

17. The invention defined in claim 13 and said blocking member, saidbiasing means and said centrifugal force responsive means in said secondposition of said blocking member being located entirely within saidinner shrouds.

References Cited in the file of this patent UNITED STATES PATENTS

1. IN A FLUID DRIVE FOR TRANSMITTING TORQUE, A DRIVING MEMBER, A DRIVENMEMBER, A BLADED PUMP ROTOR CONNECTED TO THE DRIVING MEMBER AND A BLADEDTURBINE ROTOR CONNECTED TO THE DRIVEN MEMBER AND MOUNTED FOR ROTATION,SAID PUMP AND TURBINE ROTORS HAVING INNER AND OUTER SHROUDS DEFININGTOROIDAL FLUID FLOW PASSAGES BETWEEN SAID SHROUDS AND SAID BLADES, THEFLUID FLOW PASSAGES OF SAID TURBINE ROTOR RECEIVING LIQUID FROM THEFLUID FLOW PASSAGES OF SAID PUMP ROTOR AND RETURNING LIQUID TO SAID PUMPROTOR, AND BLOCKING MEANS INCLUDING A BLOCKING MEMBER MOUNTED ON A ROTORFOR MOVEMENT BETWEEN A FIRST POSITION AT LEAST PARTIALLY BLOCKING SAIDFLUID FLOW PASSAGES AND A SECOND POSITION SUBSTANTIALLY WITHIN SAIDINNER SHROUDS UNBLOCKING SAID FLUID FLOW PASSAGES, BIASING MEANS MOUNTEDON A ROTOR AND LOCATED IN ALL POSITIONS ENTIRELY WITHIN SAID OUTERSHROUDS FOR ENGAGING SAID BLOCKING MEMBER TO URGE SAID BLOCKING MEMBERFROM ONE TO ANOTHER OF SAID POSITIONS AND CENTRIFUGAL FORCE RESPONSIVEMEANS MOUNTED ON A ROTOR AND LOCATED IN ALL POSITIONS ENTIRELY WITHINSAID OUTER SHROUDS FOR MOVING SAID BLOCKING MEMBER FROM SAID ANOTHERPOSITION TO SAID ONE POSITION.